A method of making an assembly can include juxtaposing a top surface of a first electrically conductive element at a first surface of a first substrate with a top surface of a second electrically conductive element at a major surface of a second substrate. One of: the top surface of the first conductive element can be recessed below the first surface, or the top surface of the second conductive element can be recessed below the major surface. Electrically conductive nanoparticles can be disposed between the top surfaces of the first and second conductive elements. The conductive nanoparticles can have long dimensions smaller than 100 nanometers. The method can also include elevating a temperature at least at interfaces of the juxtaposed first and second conductive elements to a joining temperature at which the conductive nanoparticles can cause metallurgical joints to form between the juxtaposed first and second conductive elements.

A method of making an assembly can include juxtaposing a top surface of a first electrically conductive element at a first surface of a first substrate with a top surface of a second electrically conductive element at a major surface of a second substrate. One of: the top surface of the first conductive element can be recessed below the first surface, or the top surface of the second conductive element can be recessed below the major surface. Electrically conductive nanoparticles can be disposed between the top surfaces of the first and second conductive elements. The conductive nanoparticles can have long dimensions smaller than 100 nanometers. The method can also include elevating a temperature at least at interfaces of the juxtaposed first and second conductive elements to a joining temperature at which the conductive nanoparticles can cause metallurgical joints to form between the juxtaposed first and second conductive elements.

Embodiments include an electronic system and methods of forming an electronic system. In an embodiment, the electronic system may include a package substrate and a die coupled to the package substrate. In an embodiment, the electronic system may also include an integrated heat spreader (IHS) that is coupled to the package substrate. In an embodiment the electronic system may further comprise a thermal interface pad between the IHS and the die. In an embodiment the die is thermally coupled to the IHS by a liquid metal thermal interface material (TIM) that contacts the thermal interface pad.

Embodiments include an electronic system and methods of forming an electronic system. In an embodiment, the electronic system may include a package substrate and a die coupled to the package substrate. In an embodiment, the electronic system may also include an integrated heat spreader (IHS) that is coupled to the package substrate. In an embodiment the electronic system may further comprise a thermal interface pad between the IHS and the die. In an embodiment the die is thermally coupled to the IHS by a liquid metal thermal interface material (TIM) that contacts the thermal interface pad.

A composite integrated circuit (IC) structure includes at least a first IC die in a stack with a second IC die. Each die has a device layer and metallization layers interconnected to transistors of the device layer and terminating at features. First features of the first IC die are primarily of a first composition with a first microstructure. Second features of the second IC die are primarily of a second composition or a second microstructure. A first one of the second features is in direct contact with one of the first features. The second composition has a thermal conductivity at least an order of magnitude lower than that of the first composition and first microstructure. The first composition may have a thermal conductivity at least 40 times that of the second composition or second microstructure.

Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.

Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second metallic interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.

A structure of a semiconductor package is disclosed. The structure includes a first substrate including a first interconnect structure. The structure includes a second substrate including a second interconnect structure, the second substrate bonded to the first substrate. The structure includes a connection pad interposed between the first interconnect structure and the second interconnect structure. The connection pad includes a material configured to switch between a high resistance state and a low resistance state. The material of the connection pad includes a phase change material.

A method of making an assembly can include juxtaposing a top surface of a first electrically conductive element at a first surface of a first substrate with a top surface of a second electrically conductive element at a major surface of a second substrate. One of: the top surface of the first conductive element can be recessed below the first surface, or the top surface of the second conductive element can be recessed below the major surface. Electrically conductive nanoparticles can be disposed between the top surfaces of the first and second conductive elements. The conductive nanoparticles can have long dimensions smaller than 100 nanometers. The method can also include elevating a temperature at least at interfaces of the juxtaposed first and second conductive elements to a joining temperature at which the conductive nanoparticles can cause metallurgical joints to form between the juxtaposed first and second conductive elements.

Devices and techniques including process steps make use of recesses in conductive interconnect structures to form reliable low temperature metallic bonds. A fill layer is deposited into the recesses prior to bonding. First conductive interconnect structures are bonded at ambient temperatures to second conductive interconnect structures using direct bonding techniques, with the fill layers in the recesses in one or both of the first and second interconnect structures.